Related Rule
South Africa
Practice Relating to Rule 77. Expanding Bullets
South Africa’s LOAC Manual (1996) provides: “Weapons which are calculated to cause unnecessary suffering are illegal per se. Such weapons include … dum-dum bullets.” 
South Africa, Presentation on the South African Approach to International Humanitarian Law, Appendix A, Chapter 4: International Humanitarian Law (The Law of Armed Conflict), National Defence Force, 1996, § 34(f)(i).
South Africa’s Revised Civic Education Manual (2004) states:
i. Prohibited Weapons. The following weapons have been prohibited:
(2) Expanding Bullets. The Hague Declaration outlawing them in 1899. 
South Africa, Revised Civic Education Manual, South African National Defence Force, 2004, Chapter 4, § 56(f)(i).
South Africa’s LOAC Teaching Manual (2008) states:
3. Means and Methods of Warfare
Several specific weapons are governed by specific treaties. These treaties establish two categories of weapons, to wit[:]
- Weapons of which the use is totally prohibited; and
- Weapons of which the use is permitted under certain conditions.
Weapons of which the Use is Totally Prohibited
- Bullets that expand or flatten easily in the human body, such as bullets with a hard envelope, which does not entirely cover the core or is pierced with incisions, eg “dum-dum” bullets. (Hague Declaration dated 29 July 1899.) 
South Africa, Advanced Law of Armed Conflict Teaching Manual, School of Military Justice, 1 April 2008, as amended to 25 October 2013, Learning Unit 3, p. 174.
South Africa’s ICC Act (2002) reproduces the war crimes listed in the 1998 ICC Statute, including “employing bullets which expand or flatten easily in the human body” in international armed conflicts. 
South Africa, ICC Act, 2002, Schedule 1, Part 3, § (b)(xix).